Machi excelled during his nine-game Giants stint, recording a 1.74 ERA. But keeping him would have expanded the pitching staff to 13 while leaving San Francisco a reserve short.

Manager Bruce Bochy acknowledged that he and the club's braintrust discussed the possibility of trimming a reserve to keep Machi on the staff. Bochy pointed out that making that kind of move remained within the realm of possibility.

"We always have that ability, if we think we're in a box and need another arm, [to] make that move at another time," he said.

And when the Giants make that move, Machi has a good chance to return.

"It's nice to have a guy down there who we know can pitch here," Bochy said. "It gives us that confidence to call him up anytime."

Mourning his grandmother, who suffered a fatal heart attack, Mijares went on bereavement leave after the April 28 game at San Diego, where he made his last appearance. He was moved to the restricted list Monday when the Giants determined that he would not arrive at AT&T Park in time for that night's game.

Bochy wasn't concerned about Mijares' inactivity, which included not throwing while he was on leave in Venezuela. Bochy said that Mijares probably could regain some sharpness by performing "touch and feel" drills, which require a pitcher to throw at 60 percent of his usual intensity.

Chris Haft is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.